I know how you're feeling. It happens to me quite often. I randomly hear something about death and suddenly there seems to be no point in anything, because no matter what it's all going to end. I've gone months straight of not being able to think anything except that, but it turns around eventually. You're in a bad place right now and I wish there was something I could say to make you feel better. Everybody dies, but it IS possible to enjoy some things in life. It may not seem like it right now but eventually it will get better. Now turn off that sad music! It's doing more harm than good.